Good Luck with doing that to Pakistan !
We didn't build the Nuclear Bomb to keep it on the shelf...we build it to nuke anyone if Pakistan were to be broken apart !
But then again we won't need to do something like that Our Pashtuns would never join the Afghans but parts of Afghanistan may cede to Pakistan because we've got twice as many Pashtuns are they do ! And the Baloch are too well integrated with the rest of Pakistan with millions of them in other Pakistani provinces for it to break away; not to mention only a small portion of 3 tribes out of dozens of tribes of Balochistan are fighting the Pakistani state & even then giving up arms & surrendering themselves so that they may be rehabilitated back into the developments the army has made in those areas from school & colleges to hospitals.